Treatment of textile and other material



Patented Mar. 13, 1934 UNITED STATES PATENT OFFICE TREATBIENT OF TEXTILE AND OTHER MATERIAL tion of Delaware No Drawing. Application August 15, 1930, Serial No. 475,630. In Great Britain August 27, 1929 Claims.

g esses.

According to the present invention the sizing or like treatment of filaments, threads, yarns, fabrics or other textile or other materials is accomplished by a process comprising the applica- 19 tion of aqueous solutions or dispersions of cellulose acetate or other cellulose esters or of cellulose ethers. It has been found that textile materials sized in this manner, for example warp threads, resist very well such mechanical treatment as is experienced, for instance, in weaving, but that nevertheless the size can be readily removed by a mild scouring process and does not interfere with subsequent dyeing of the materials.

Cellulose esters or ethers soluble or dispersible in water may, for example, owe their watersolubility or water-dispersibility to their cellulose content being more or less degraded or to the presence of substituent groups imparting watersolubility or water-dispersibility, or to both causes simultaneously.

Thus cellulose acetates or other cellulose esters or cellulose ethers capable of solution or dispersion in water may be obtained by suitably degrading or degrading and hydrolyzing the known water insoluble cellulose acetate orother esters or cellulose ethers. Esterification products of cellulose are commonly subjected to a ripening process for the purpose of changing their solubilities in various solvents and particularly for the purpose of rendering cellulose acetate soluble in acetone. Products suitable for application in accordance with the present invention may be obtained by continuing such ripening processes beyond the acetone soluble stage at which this operation is normally terminated, until products capable of yielding solutions or dispersions with water are obtained. On the other hand, this ripening process should not be carried too far if the most satisfactory results are to be obtained in the sizing of the textile or other materials. Over-ripening may lead to the formation of products of comparatively low adhesive power. It may be here mentioned that a very satisfactory sizing medium is in practice obtained by carrying out the ripening process so as to obtain a prod- 7 not which, while readily soluble or dispersible in this manner but which leave merely sticky deposits, are less suitable for the purpose of the present invention.

The hydrolysis and/or degradation of the cellulose esterification or etherification products may be conducted in various ways, for example by treatment with water in the presence of suitable hydrolytic agents, e. g. acids such as sulphuric acid. Thus, for instance, a solution of cellulose acetate in strong acetic acid may be treated with a small quantity of sulphuric acid and allowed to stand at ordinary or slightly elevated temperatures, further additions of water being made as the ripening process proceeds. Very conveniently there may be employed the acetic acid solutions of cellulose acetate containing a small amount of sulphuric acid such as are obtained by the direct acetylation of cellulose with acetic anhydride in the presence of acetic acid using sulphuric acid as catalyst. Such a solution may, for example, be diluted with acetic acid to reduce its viscosity and stirred with addition of water from time to time as may be necessary. Preferably the ripening should be carried out as uniformly as possible, as otherwise part of the material is liable to become over-ripened before the main bulk has become sufficiently soluble or dispersible in water. The time required to obtain a satisfactory degree of ripening will vary very widely depending upon the conditions under which the reaction is effected.

Where the preparation of the sizing material has been effected in the presence of acetic or other acid, this should preferably be eliminated from the product prior to use. Such elimination of acid may be eifected in any desired manner, for example the ripened solution may be subjected to dialysis, e. g. through parchment paper or other membrane. Acetic and other organic acids may also be eliminated from the solutions by extraction with solvents, for example ether. Alternatively the product may be isolated in solid form from the acid solution in which hydrolysis and/or degradation has been efiected, and the products redissolved in water for employment as sizes. Such isolation of the product may be attained, for example, by salting out or by addition of a suitable liquid miscible with the solution and in which the product is insoluble.

Cellulose derivatives suitable for use in accordance with the invention may also be prepared by esterifying or etherifying cellulose under conditions such that degradation of the cellulose molecule occurs and derivatives soluble or dispersible in water are directly produced. Thus for examnle cellulose may be esterified with acetic or other fatty acid at relatively high temperatures and/or in the presence of relatively large proportions of sulphuric acid or other agents having a degrading action on cellulose or cellulose derivatives,v

Again if desired cellulose may be degraded, e. g. by treatment with alkalis or acids, prior to esterification for the production of the required watersoluble or water-dispersible cellulose derivatives.

As previously indicated cellulose derivatives soluble or dispersible in water may also be used which contain ester or ether groups having radicles e. g. carboxyl or hydroxyl radicles, imparting water-solubility or water-dispersibility. For instance cellulose may be esterified, e. g. in the present of chloroacetic anhydride, -with dicarboxylic acids for example oxalic acid or maleic acid; or a cellulose acetate may be subjected to the action of a hydroxy carboxylic acid e. g. glycollic acid, lactic acid, malic acid, mandelic acid, a tartaric acid or a glyceric acid, so as to replace acetic acid residues by the corresponding hydroxy carboxylic acid residues. Likewise cellulose may be etherified so as to contain residues of glycols or other polyhydric alcohols, for example in the manner described in U. S. Patent No. 1,502,379 and application S. No. 162,214 dated January 19th, 1927, of Dr. Henry Dreyfus, or cellulose may be etherified with carboxy-alkyl groups, for example alkali cellulose may be treated with chloroacetic acid so as to produce cellulose derivatives containing 1 to 2 or more carboxymethylether groups per CcHmOs molecule.

In general it is found that the most satisfactory results are obtained by sizing with cellulose esters or ethers which give aqueous solutions or dispersions yielding films on evaporating the aqueous media.

Aqueous solutions or dispersions of esterification or etherification products of cellulose, whether products obtained by direct esterification or etherification under suitable conditions or products obtained by suitably hydrolyzing and/or degrading water insoluble cellulose esters or ethers may be employed for the sizing of yarns, filaments, threads, fabrics or other textile or other materials in any convenient manner. For example, the yarns or the like may be treated in hank form with the solutions, or they may be passed continuously through the solutions and subsequently subjected to a drying operation. One application of the new sizing solutions is to the sizing of artificial filaments, yarns or the like continuously with their production. For example a solution of cellulose acetate in acetone may be spun into an evaporative atmosphere and the sizing solution applied continuously to the filaments as they leave the spinning apparatus and prior to their being wound or twisted and wound (see U. S. Patent No. 1,506,052 of Dr. H. Dreyfus).

The new process of sizing may be applied to textile materials made of any desired filaments or fibres whether natural or artificial. The invention is however of particular value in the sizing or other ester or methyl, ethyl or benzyl cellulose or other ether of cellulose.

As mentioned previously the sizes applied to textile materials in accordance with the invention may, if required, readily be removed. For example removal may be effected by scouring e. g. in anaqueous soap solution. In some cases, for example where the cellulose ester or ether used as size contains carboxyl or hydroxyl groups in the esterifying or etherifying radicals, removal may be assisted by alkalis. Very small concentrations of alkali may have a beneficial action inthe removal of the size, a great advantage in the treatment of materials made of or containing cellulose esters or other materials liable to damage by strongly alkaline solutions.

The following examples illustrate the preparation of a sizing liquid from cellulose acetate in accordance with our invention.

Example 1 A 15-25% solution of cellulose acetate in acetic acid and containing sulphuric acid as directly obtained, for example, in the acetylation of cellulose, is diluted in the cold with 5% of its weight of water and allowed to stand at ordinary temperature. Subsequent additions of water are made at intervals until at the end of 3-4 weeks a solution is obtained containing about 5% of 300 cellulose acetate. The acid is then substantially removed by extraction with ether, or by dialysis or both. The resultant liquor may then be employed for sizing warp threads or other material either directly or after concentrating or diluting as desired or requisite. I

Example 2 A 15-25% cellulose acetate, solution is directly obtained by acetylation of cellulose with acetic no anhydride in presence of acetic acid and sulphuric' acid is diluted with 50% acetic acid until it is of a suitable consistency for stirring. The mixture is then kept at 50 C. with constant stirring, with additions of water from time to time as ripening proceeds. At the end of 35 to 45 hours the acetate will have become sufiiciently soluble in water and the product may be further treated and utilized as in Example 1.

What we claim and desire to secure by Letters Patent is:-

' 1. Process for sizing threads, filaments, yarns, fabrics and other textile materials comprising an organic derivative of cellulose, which comprises applying thereto carboxylic esters of cellulose containing ester radicles having as a substituent at least one radicle selected from the group consisting of carboxyl and hydroxyl radicles imparting solubility in aqueous liquids to the cellulose esters.

2. Process for sizing threads, filaments, yarns, fabrics and other textile materials comprising an organic derivative of cellulose, which comprises applying thereto carboxylic esters or cellulose, containing ester radicles having as substituents carboxylic groups.

3. Process for sizing threads, filaments, yarns, fabrics and other textile materials comprising an organic derivative of cellulose, which comprises applying thereto carboxylic esters of cellulose containing ester radicles having as substituents hydroxyl groups.

4. Process for sizing threads, filaments, yarns, fabrics and other textile materials comprising cellulose acetate, which comprises applying thereto carboxylic esters of cellulose containing ester radicles having as substituents carboxylic groups.

5. Process for sizing threads, filaments, yarns, fabrics and other textile materials comprising cellulose acetate, which comprises applying there- 150 to carboxylic esters of cellulose containing ester radicles having as substituents hydroxyl groups.

6. Process for sizing filaments comprising cellulose acetate, which comprises applying thereto carboxylic esters of cellulose containing ester radicles having as a substituent at least one radiole selected from the group consisting of carboxyl and hydroxyl radicles continuously with theproduction oi the filaments.

7. Filaments, threads, yarns, ,fabrics and other textile materials comprising an organic derivative of cellulose sized with cellulose carboxylic esters containing ester radicles having as a substituent at least one radicle selected from the group consisting of carboxyl and hydroxyl radicles.

- 8. Filaments, threads, yarns, fabrics and other textile materials comprising an organic derivatlve of cellulose sized with cellulose esters wherein the cellulose is at least partially esterified by a hydroxy carboxylic acid.

9; Filaments, threads, yarns, fabrics and other textile materials comprising an organic derivative of cellulose sized with cellulose esters wherein the cellulose is at least partially esterlfled by tartaric acid.

10. Filaments, threads, yarns, fabrics and other textile materials comprising cellulose acetate sized with cellulose carboxylic esters containing ester radicles having as a substituent at least one radicle selected from the group consisting of carboxyl and hydroxyl radicles. 

